Bobbin winding machine



Feb. 23, 1954 e. c:. JOYCE 2,670,147

BOBBIN WINDING MACHINE Filed Dec. 8, 1951 7 Sheets-She et 1 r I. 5 I

M IN C a a o Jill-HF $325 7 a ,7 6 SM-' I 3 ii m Ll.

Fig.2

INVENTOR.

CLOVER C. JOYCE.

B Y 44w. 2%

ATTY.

Feb. 23, 1954 G. c. JOYCE 2,670,147

BOBBIN WINDING MACHINE Filed Dec. 8, 1951 I 7 Sheets-Sheet 2 #:r". lllll-lIll INVENTOR. CLOVER c. JOYCE.

- ATTY.

Feb. 23, 1954 c JQYCE 2,670,147

BOBBIN WINDING MACHINE Filed Dec. 8, 1951 7 Sheets-Sheet 3 Fig l2 INVENTOR.

- CLOVER 'CUGYCE.

Feb. 23, 1954 G. C. JOYCE BOBBIN WINDING MACHINE Filed Dec. 8, 1951 7 Sheets-Sheet 4 Fig. I6

INVENTOR. GLOVER C. JOYCE.

ATT'Y.

Feb. 23, 1954 G. c. JOYCE BOBBIN WINDING MACHINE 7 Sheets-Sheet 5 Filed Dec. 8, 1951 INVENTOR. CLOVER C. JOYCE. .63

ATT'Y.

Feb. 23, 1954 c, JQYcE 2,670,147

BOBBIN WINDING MACHINE v Filed Dec. 8, 1951 7 Sheets-Sheet 6 INVENTOR. CLOVER C. JOYCE.

. Feb. 23, 1954 c, JOYCE 2,670,147

BOBBIN WINDING MACHINE Filed Dec. 8, 1951 7 Sheets-Sheet 7 INVENTOR.

CLOVER CJOYCE.

BY 631w,

Patented Feb. 23, 1954 'fGlover 0. Joyce, Worcester, Mass.,

assignor to Whitin Machine Works,Whitinsville, Mass., a corporation of 'Massachusetts :Application December 8, 1951, Serial No. 260,719

8 Claims. 1

This invention relates to a machine for winding thread or yarn on bobbins, and particularly. for winding weft .or fillingyarn on loom bobbins. Such bobbins are commonly tapered and one important object of my invention is to. provide improved mechanism for winding a cylindrical yarn package on a taperedibobbin.

. Another object is to provide means for easily adjusting and adapting the winding machine to 'operateon bobbins of different sizes and tapers.

.Other features of the invention relate to the provision of an improved thread-guide-carriage and high-speed operating means therefor; to the provision of .improved means forvariably feeding the thread guide carriage as "the winding progresses; and to the provision ofimproved stoppingand resetting-mechanism which is automatically rendered operative when the winding of a bobbin iscompleted. The entire design of the machine is also particularly; adapted to-very high speed operation and with correspondingly increased production.

My invention further relates to certain arrangements and combinations of parts which will be hereinafter described and more particularly set forth in theappended claims.

A preferred'fo'rm of theinvention is'shown' in the drawings, in which :Fig. 1 is afrontelevationofa preferredembodiment of the invention; 1 "Fig. 1 is a detail sectional end-view, taken along the line l -l -inFig. 1;

' Fig. 2 is an end viewplooking inthe direction of the arrow 2 in Fig. 1;

Fig. -3is a plan view-looking in the direction-of the arrows? in Fig. 1

Fig. 4 is an end'view, looking in -thedirfectio'n of the arrow 4 in Fig. 3 and having a portion of the casing removed;

"Fig. 5 is an enlarged-'front-elevation ofcertain parts shown in Fig. 1

Fig. 6 is aplan view ofthe 'mechanism'shown inFig'. 5-and partly in section substantiallyalong the line 6-6 in Fig. 5;

Fig. 7 is apartial endelevationylookinginthe direction of the arrow '1 in Fig. 5;

Fig. 13 is a plan view of a-guide plateitobe described;

Fig. 14 is a side elevation of an assembly of thread guide parts;

Fig. 15 is an enlarged sectional elevation,- taken along the line I 5-I 5 in Fig. 14;

. Fig. 16 is a similar elevation, taken along the line I 6-46 in Fig. 14; r

Fig. 17 is a perspective view of a thread. guide lever;

Fig. 18 is a perspective view of a guide plate and certain associated parts;

Figs. 19-26 inclusive are perspective views of detailed parts to be described;

Fig. 27 is a front elevation-0f a pickrmechanism;

I Fig. 28 is an irregular sectional view,.taken along the line 2828 in- Fig. 27;

Figs. 29 and 30 are front elevations ofacertain parts in partial perspective and looking inthe directions of the arrows 29- and -30 respectivelyin Fig. 28;

Fig. 31 is a perspective view of certain actuating parts of the pick mechanism;

Fig. 32 is a front view of certain partsshown in Fig. 31;

Fig. 33 is an oblique plan view'of certain parts looking in the direction Y of the arrow 33' in :Fig.

Fig. 34 is an exploded perspective viewofpcer tain feed-control mechanism;

Figs. 35 to 43 are detailed views,pa'rtlyrin-section, of certain parts shown in Fig. 3.4xandto ..be hereinafter described; and

Fig. 44 is a diagrammatic perspective view, showing the driving'relation of .the severalicomponent units or mechanisms.

The windin machine herein shown 'is adapted for winding bobbins of different diametera-lengths and tapers, and the windingsmaybeof varied outside diameters.

, An assembly of the machine in a preferred'forin is shown in Figs. '1 to 4. 'The machineas shown comprises a driving motor M, a pick unit A, a compensating and control unit B, and a thread guide carriage and control mechanism C; -'The Fig. 8 is a plan view of athread guide-carriage;

Fig. ,9 is a sectional-side elevation taken along the line 9-9 in Fig. 8;

Fig. 10 is a transverse sectionalelevation,taken along, theline I 0-. It in ,Fig. 9; E ..j. .1; is a perspective viewitofxan en ratin cam;

Fig. 12 is a development of saidcam; V

dependent uponthe' settingofytheipick unit, A

units A and B and the motor Mhave a casing or frame F, and the threadguide carriage is'slidable on a rod 50, secured to an end frame member 5| which, in turn, is secured to supportingrodsIBZ (Fig. 3) which are fixed in theframe F.

Briefly stated, the contour and'diameterpf the thread package isidetermined -by a.the. rateoirfeed of the; thread guide carriage,,jand this .;feed' is and upon the operation of the compensating and control unit B.

The thread guide carriage is fed lengthwise of the bobbin N (Fig. 44) by a rack rod 55, which is moved lengthwise by a gear 56. This gear 59 is intermittently advanced in small increments by the pick unit A through a sprocket 51, chain 58, sprocket 59, and intervening mechanism comprising the compensating and control unit B.

A gear 99 (Fig. 44) is rotated by a pinion (H on a shaft 62 driven from the motor M through a belt 63, pulley 64, spindle shaft 65, worm 96 and worm gear 61. The gear 99 is thus continuously rotated by the motor M but at greatly reduced speed during each full winding operation.

Pick unit The gear 69 is secured to a rotating member or spider 19 (Figs. 28 to 33), and th spider 19 rotates freely about the axis of a stud 12, which stud supports the sprocket 51. A plurality of pawls 14 (Fig. 31) are pivoted on studs 15 fixed in the spider 19, and each pawl 19 is moved to engage a ratchet wheel 11 by an associated spring 18 (Fig. 32).

The extent of engagement of each pawl with the ratchet wheel 11 is determined by a pair of coaeting cam plates 89 and SI mounted concentric with the stud 12. The outer cam plate 89 is fixed to the casing 92 (Fig. 28) of the pick unit A, and the inner cam plate BI is mounted on a loose bushing 84 (Fig. 28) to which is secured an index plate 85 (Figs. 1 and 27). Each cam plate 89 and BI comprises a larger concentric portion or rise 81 (Figs. 29 and 31) and a smaller concentric portion 88.

The cam plate 89, as above stated, is fixed to the casing 82, and the cam plate 8! may be angularly adjusted by manual movement of the index plate 85. When thus adjusted, the plate 85 may be secured by a clamping plate 89 (Fig. 28) and a clamping screw 81.

Each pawl 14 has a stud or roll 99 (Fig. 31) projecting therefrom and engaging the periphcries of both cam plates 89 and 8|. When the stud 99 is supported by the larger portion or rise 81 of either cam plate, the associated pawl 14 is inoperative, but when the roll 99 drops into the space between the rises 91 (which space is indicated at ain Fig. 31) the associated pawl 14 will engage and feed the ratchet wheel 11. The number of teeth fed on such engagement depends on the angularly adjusted position of the movable cam plate 8| Consequently, the rate of feed of the ratchet wheel" is determined by the setting of the cam plate 8| and may be varied from one tooth to a substantial angular movement, according to'the adjusted setting.

The pawl-supporting member or spider 19 rotates continuously, as previously explained, and at each rotation three successive pawls 14 engage and feed the ratchet wheel as their studs 99 successively enter the reduced space a between the rises 81 of the cam plates 89 and 9! By increasing the space a to its greatest limit, the feed of the ratchet wheel may be made substantially continuous, whereas by greatly reducing the space a, the feed of each pawl may be limited to a single tooth, with a net advance of three teeth for each revolution of the member 10.

Compensating and control unit The compensating and control mechanism B (Fig. 44) is inserted between the sprocket 59 (which is intermittently and regularly advanced 4 by the pick unit A) and the rack bar 55 which determines the axial feed of the thread guide carriage in the assembly C.

The main object of the compensating and control mechanism in the unit B is to provide a variable and very great speed reduction between the rotation of the ratchet wheel 59, driven by the pick unit, and the rotation of the gear 59 which actuates the rack bar 55. The construction and operation of the unit B is shown in exploded perspective in Fig. 34 and in detail in Figs. 35 to 43.

A stud 92 is mounted in the side of a disc 53 (Fig. 35) and is moved in a circular path by the sprocket 59, the disc 93 being loose on the fixed shaft 95. The stud 92 loosely supports a pair of pinions 96 and 91 (Fig. 39) which are fixed to rotate together and which commonly difier from each other by a single teeth, the pinion 91 having one more tooth than the pinion 96. The pinion 96 engages an internal gear I99 (Fig. 34) which is normally fixed. The pinion 91 engages a similar internal gear iIlI on a bushing I92 (Fig. 36) and to which bushing a gear I99 is also secured. The bushing I92 rotates freely about the axis of the fixed shaft and the gear I93 is connected by an idle or intermediate gear I95 to the gear 55, previously described as actuating the rack bar 55.

On each rotation of the disc 93 by the sprocket 59, the pinion 99 will be carried around insid of the fixed gear I99 for individual rotation thereby, and the pinion 91 will be correspondingly rotated but will relatively advance the gear IN by one tooth space thereof, by reason of the extra tooth in the pinion 91.

Hence, for each rotation of the sprocket 59 and disc 93, the gear I9I advances one tooth space thereof. The disc 93 must thus perform a plurality of revolutions (perhaps 50 or more) to advance the gear II" a single revolution.

7 Compensation for bobbin taper In the usual operation of the winding machine, the barrels of the bobbins are tapered, but it is desired that the outer surface of th yarn package shall be cylindrical, so that a maximum amount of yarn may be placed on a bobbin within the width limit established by the shuttle cavity.

Special compensating mechanism is accordingly provided by which the rate of feed of the rack bar 55 may be decreased as the diameter of the bobbin grows less, with the result that the slower axial feed of the thread guide carriage will increase the amount of yarn wound on the bobbin and thus offset the decrease in bobbin diameter.

For this purpose, the gear I99 is mounted for limited angular movement and is shown diagrammatically in Fig. 44 as being provided with an arm I91 engaged by a cam I98 on the shaft H9 which supports the gear 56 and rotates therewith. As the gear 56 rotates and effects the carriage feed, the cam I98 is correspondingly rotated and allows the arm I91 to move counter-clockwise, which has the effect of bodily moving the gear I9I similarly counter-clockwise. This to some extent offsets the regular feed by the pick unit A and slows down the travel of the thread guide carriage.

By varying the contour of the cam I99, the machine may be adapted to provide a cylindrical winding on bobbins of varied size and taper, and by changing the earns the utility of the machine may be increased.

.In :the? modifiedi'construction islioivn ;in:' 1' ig.-i%34'; provision ismade for'rproportionately varyingi the :eifect of eaclr cam: I 08 Inthis construction the cam I08, instead of 'fdirectlyactuating the intern'a'lgear. I; engages apin I=I:2 in a lever II3 pivotedat II-4. A'linkrIIG is connected at 'o'ne end to a stud I I! in. aniarm =I I8ffixed to the gear I00 and corresponding tothe arm l 0lprevi'ously described. The otherlend'of the link I I6is pivoted on a stud I which isadjustable in aira'dial slot I2 I 'on the arm I I3.- By varying the ipositionof the stud- I20 in the-slot I2l,"the effect of th'e cam I08 may be substantially increased or decrease'd as desired for bobbins of diiferent taper. The

Return movementof the thread guide carriage Provision is'made for prompt-returnmovement of the thread guide carriage attheendof each winding operation. For this purpose-pacam I (Fig. 34) on a cam shaft I 3| is given a'single revolution by knock ofi mechanism to be de scribed and aseach bobbin winding is completed.

' The intermediategear I05 (Figs.- 42 "and-43 is mounted on astud I32 at the end of an'arm I33 mounted'to swing-about the'axis of the sha'ft95.

An offset portion: I35 of thearm- I33'has a stud I36 which extends through aslot'in a bell crank lever 'I3'I-'-(Fig."34) mounted on a fixed pivot I38.

The free "end I40 of the bell'crankiever I3 1" engages the cam I30, which ismainly-"circular; but which has a raised portion MI. When-the raised portion I4I engages the free end I40 'of'the 'bell crank, the arm I33 will beswungon the axis of theshaft 95 and the intermediate gear I 05will'be thu's disengaged from the gear 56'on'the shaft I I0 which shifts the rack'bar-55. Theshaft 'IIII (Fig. 34) also s'upports th'e feed control cam- I08.

A clock spring I43 is secured atoneendtd the shaft H0 and at'its opposite end to a 'fixe'd'rod I44. -As soon as the intermediate gear I05 is moved downward to clear the gear 56; the spring I43 promptlyrotates the shaft IIO anti-clock wise to reset the cam I08 and to return the rack bar 55 to initial position.

Thread guide carriage The construction of the thread guide .carriage is shown in Figs. 8 to 26. The carriage comprises acasing I (Figs. 8 and 9) 'mounte'd'at the tubular end I5I of the rack bar and slidable therewith on the supporting rod :50 previously described. The casingl50hasa transversely; extending bushing I53 (Fig. 10): having ahexagonal opening therethrough to receive ahexagonal driv in'g'shaft I54. I

Acam I55 (Figs. 10'and 11) "having a doublethrow peripheral cam'g'roove' I58 is "mounted'on the bushing I53 and is thus rotated with "the hexagonal shaft I54. Aroll I56 i'simountedf on the lower end'of a stud I51 (Figs. 9 and 20)."and is received in"the"peripheral cam groove I 58; ""L'The stud- I51 ismountedincneiend"of 'ana'rm I60 (Fig. '24) which is" pivoted on a iheaded bushing I6 I (Fig. 26 which is'secured' to a platel 52 by arbindingesersvv .sI 63- (Fig'. 5239'.- aTheiplat'e-il62-fis fixed iiilth'eicarriageacasing.,

The upper end of thestudr I51 is receivedin a. rbearin'g 0peningi165 ?QFiEJ 1'7 in a. lever- I166: havving 'aithreadeguiderG mounted; in'one end-thereof. The :1ever I66 also has an e1ongatedslotnI68 to -receive" a 'stud I '6 9 :(Fig. 19 )3 which. also extends through -akwasher 5110 (Fig. .21-) "and which is 'thre'aded ina nu't' I I I (Fig. 2-2) the upper portion ma'ybe adjusted longitudinally :of the. slot "2 to change the position of the pivot and .thus vary theflthrow of th'e' thread guide G. As the *slot' I'I2 is alignedwith" the starting .position 'of the thread guide GA (which is shown in full lines in'Fig'.-'8) the thread'iguide G will always return to 'athis-i position, regardless of the adjustment of the pivot-r'stud' lfiii. Consequently all variations in length ofthrow ofithe'thread guidetake'place 'at' the o'pposite :endof the strokeor at the end toward the tip .of the bobbin.

The cam grooveI58 in the 'cam'I'55 isshown developed in Fig..12 ,:*where it-will be'noted that the two irises oi ithe .c'am groove indicated .at points I15 and: FIB-rare at slightly: different elevations.. The-effect :of this is to slightly :shift successive windings axially. relative to each other, so that an improved locking'of thewindingscisvthereby attained. The threads oi =each windinglay between the threads'in the next ad- .j-acent winding. with theithread 'guide carriage and associated mechanism C constructed as above-described, thew'th'read guide Gi c'aniibe very rapidly oscillated by rthe hexagonaldriving shaft I 54 in every longitudinal-position "ofithe :carriage, and the throw of "the thread. guide G may :beadjusted within wide Iim'its by changing the setting" of the stud I69. .Furthermore; in everyiposition of :the stud as-rpreviously described, "the starting position of the thread guide G' willub'e the. full. line position shown-in.=Fig. 8. r I 1 Driving mechanism Theassembled driving mechanism is shown diagrammatically in Fig; 44 and in its actual relationship in Fi s.--r to 4'. j

Referring to Fig-44, themotor M'has an armature shaft I which' continuously rotates a small pulley which drives a countershaft.-- I8I through ab'elt' I82. The shaft I8I has a worm I84-engaginga worm wheel. I85 on a shortshaft I86. A'smallpulley" I 81 on theshaft -I8Ii is conne'cted"by"a"heltrI88"to a larger pulleyl89 loose *onthe camshaft I'3I previously described. The ,pulley"I89, is thus .rotated continuously by the motoifMfbut at substantially reduced speed. ":The' :belt Ii3'fpreviou'sly described .is' drivenb'y a pulley" I92" loose onthe'armature shaft I80 but adapted to"'be'clutched"thereto by control devices to-he described; The shafts'62 'and'i65 are thus rotated only during the'winding operation.

' "Theshaft 62 controls the longitudinal mo've-. 'nientof the. rack bar'i55 and the associated yarn id i ig' through thc piCknnit A. and coma p'ensatin tiunitj; "n'gpre'viously' described. shaft "62 is also .icorinected' through spiral gears 195;shaft"l'96 and spur'gears fat-491' to the hexagonal shaft [54 which drives the doublethrow cam I55 to oscillate the thread guide lever I66 and thread guide G.

The cam shaft I3I is normally stationary and is held from rotation by a lever 200 mounted in a collar or drum I fixed to the shaft I3I and normally held from movement by a bell crank lever 202 pivoted on a fixed shaft 203. A notched disc 205 is normally rotated continuously with" the pulley I89. Whenever the bell crank 202 is moved to release the latch 200, the latch will be swung outward by a spring 204 and will be engaged in one of the notches in the disc 205. Such engagement causesthelatch 200 and its supporting drum 20I on the shaft I3I to perform a single revolution, on the completion of which the bell crank 202 forces the latch 200 away from the notched disc and the shaft I3I returns to rest.

Duringthis single revolution, the cam 130 on the shaft I3I operates through suitable connections (shown digrammatically in Fig. 44 at 201; 208 and 209) on the arm I33 (Fig. 42) and disengages the intermediate gear I05, thus stopping the feed and allowing return movement of the rack bar 55 and the thread guide carriage. The connections 207; 208 and 209 are shown only diagrammatically in'Fig; 44 and are in correct proportion in Figs. 34 and 40.

Disengagement of the stopping bell crank 202 from the latch 20!) is effected by the operation of a push rod -2I0 (Fig. 44) having a collar 2Hl which is engaged by the thread guide carriage as it reaches its desired limit of travel. The collar 2Ill is adjustable to vary the travel.

The rod 2I0, when thus engaged, swings a lever 2 on its pivot 2I2. The opposite end of the lever 2II has a link 2I4 which is connected to a depending arm of the bell crank 202, thus releasing the latch 200.

As the cam shaft I3I makes its single revolution, a cam 220 releases a bell crank 22I for operation by a spring 222 to shift a push rod 223 to release the motor clutch and to apply a brake 224 (Fig. 1 to the driving pulley I92. This promptly stops rotation of the bobbin-driving shaft 65, as well as the operations of the pick unit A and the compensating unit B.

A third cam 230 (Fig. 44) on the cam shaft I3I operates a lever 23I to shift a second lever 232 to withdraw the tail carrier 233 which normally supports the tip of the bobbin N. The bobbin then drops out of the winding machine and may be replaced by hand, or by suitable loading mechanism, not shown herein.

Operation The operation and advantages of my improved winding machine will be readily apparent from the foregoing detailed description. Assuming that a fresh bobbin has been associated with the driving spindle 65 (Fig. 3), the motor M will then rotate the spindle and bobbin at a very high speed which may reach 12,000 revolutions a minute, and the thread guide G will be rapidly oscillated in the thread guide carriage to lay the thread or yarn in successive layers on the bobbin. The movement of the thread guide is effected by the hexagonal driving shaft I54.

At the same time, the pick unit A gradually feeds the thread guide carriage to the right in Fig. 3 (or toward the tip of the bobbin), and the rate of feed is varied and controlled by the cam I08 (Fig. 34) in the compensating unit B.

When the winding of the bobbin is completed,

thethread guide carriage-engages a'colla'r III) (Fig. 1-) and through suitable connections moves the latch 202 (Fig. 44) to release the cam shaft I3I for a single revolution.

During this single revolution, the cam I30 releases the thread guide carriage feed, so that the carriage can return to its initial or left hand position as viewed in Figs. 3 and 44; the cam 220 disconnectsand brakes the driving pulley I92; and the cam'230 withdraws the tail center or bobbin support 233 from the tip of the bobbin, thus allowing the bobbin to fall out of the winding machine.

A fresh bobbin is then inserted, either manually or automatically, and the described cycle of events is then repeated. The entire machine is particularly designed for high speed operation, and the output of the machine is correspondingly large.

The quick-traverse'mechanism herein shown is not claimed in this application but forms the subject matter of a divisional application Serial No. 307,327; filed August 30, 1952.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed otherwise than as set forth in the claims but what I claim is:

1. A bobbin winding machine comprising a winding spindle, means to rotate said spindle, a thread guide, athread guide carriage, means to oscillate said guide in said carriage, means to shift said carriage progressively toward-the tip of the bobbin being wound, additional automatic mechanical means to vary the rate of progressive shifting of said carriage as the winding proceeds, and automatic means to stop the winding operation at the end of a predetermined extent of carriage shift.

2. The combination in a bobbin winding machine as set forth in claim 1 in which the shiftvarying means includes a continuously rotating cam and a coacting member effective to vary the rate of shift.

3. The combination in a bobbin winding machine as set forth in claim 1 in which the shiftvarying means includes a cam and a coacting member efiective to vary the rate of shift and in which adjustable leverage devices are provided between said member and said carriage effective to proportionately vary the action of said cam.

4. The combination in a bobbin winding machine as set forth in claim 1 in which the shifting means includes a connected pair of separate and slightly unequal pinions which are swept together around a circular path, a normally fixed internal gear and a movably mounted internal gear respectively engaged by said separate pinions, whereby said movable gear receives a differential rotary motion, and means to impress a limited angular movement on the normally fixed gear.

5. The combination in a bobbin winding machine as set forth in claim 4 in which the normally fixed internal gear is supported in a casing which encloses both internal gears and both pinions, and in which the limited angular movement of the normally fixed gear is imparted thereto by angularly shifting the enclosing cas- 6. In a bobbin winding machine, a thread guide, a thread guide carriage, and means to shift said carriage progressively toward the tip of the bobbin to be wound, and said shifting means including a ratchet wheel, a pawl, a support therefor rotating about the axis of said ratchet wheel, a

fixed cam having concentric high and low porti0ns, a second cam mounted concentric with said first cam and similarly contoured, and contact means associated with said pawl and holding said pawl inoperative except when said contact means is out of contact with the high portions of both cams.

'l. The combination of a bobbin winding machine-as set forth in claim 6 in which the second cam is mounted for manual angular adjustment about the common axis of said cams to vary the peripheral extent of the low space between the high portions of the two cams.

8. In a bobbin winding machine, a thread guide. a thread guide carriage, and means to shift said carriage progressively toward the tip of the bobbin to be wound, and said shifting means including a ratchet wheel, a plurality of pawls, a support therefor rotating about the axis of said ratchet wheel, a fixed cam having concentric high 20 and low portions, a second cam mounted concentric with said first cam and similarly contoured, and contact means associated with each pawl and holding said pawl inoperative except when said contact means is out of contact with the high portions of both cams.

GLOVER C. JOYCE.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 458,927 Whyte Sept. 1, 1891 494,723 Rosskothen Apr. 4, 1893 976,698 Ryon Nov. 22, 1910 1,214,742 Altemus Feb. 6, 1917 1,236,906 Calkins Aug. 14, 1917 2,011,429 Walton et al. Aug. 13, 1935 2,267,899 Dersen Dec. 3, 1941 2,609,156 Kimpton Sept. 2, 1952 FOREIGN PATENTS Number Country Date 481,232 Great Britain Mar. 8, 1938 900,111 France Sept. 18, 1944 

